Abstract
The question of material stability is of fundamental importance to any analysis of system properties in condensed matter physics and materials science. The ability to evaluate chemical stability, i.e., whether a stoichiometry will persist in some chemical environment, and structure selection, i.e. what crystal structure a stoichiometry will adopt, is critical to the prediction of materials synthesis, reactivity and properties. Here, we demonstrate that density functional theory, with the recently developed strongly constrained and appropriately normed (SCAN) functional, has advanced to a point where both facets of the stability problem can be reliably and efficiently predicted for main group compounds, while transition metal compounds are improved but remain a challenge. SCAN therefore offers a robust model for a significant portion of the periodic table, presenting an opportunity for the development of novel materials and the study of fine phase transformations even in largely unexplored systems with little to no experimental data.
Highlights
Accurate first-principles stability calculations are critical to the studies of materials synthesis,[1] reactivity[2,3] and properties,[4] and essential for both the exploration of new chemical spaces and the study of difficult-to-observe phases
Errors in formation enthalpy predicted by PBE are usually at the level of ~0.2 eV/atom, which leads to significant errors in predicting phase stability among dissimilar chemistries
Self-interaction error manifests itself in transition metal compounds, especially in semiconducting and insulating oxides, more than in main group compounds due to the presence of valence d electrons that localize more than valence sp electrons.[50]
Summary
Accurate first-principles stability calculations are critical to the studies of materials synthesis,[1] reactivity[2,3] and properties,[4] and essential for both the exploration of new chemical spaces and the study of difficult-to-observe phases. We show that the SCAN30 semilocal density functional halves the errors of PBE in predicting formation enthalpies of about 200 binary solids,[15] taking a significant step towards chemical accuracy while retaining a comparable efficiency to PBE.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
